Gemstones and precious metals
Tests: 5 of 11 right · Exam: 1 of 4 right · Kind: plain · Understood: 7 of 15 · Run: 2026-10-18, commit f3c23ea72
Lesson 51 of the geography course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.
Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.
Test 1 · wrong ✗
Jake reckons diamonds and pencil lead are totally different stuff. right?
- 1. Yes, diamond is a frozen liquid — ← Mova's choice · no support
- 2. Yes, pencil lead is real lead metal — no support
- 3. Yes, diamond is made of crushed glass pressed hard — no support
- 4. No, both are carbon, just arranged differently — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 2 · wrong ✗
lol my cousin says sapphires r just blue rubies basically. is she wrong
- 1. Totally wrong, they're nothing alike — ← Mova's choice · no support
- 2. Totally wrong, sapphire is a kind of diamond, ruby isn't — no support
- 3. Totally wrong, sapphire is coloured glass, not a gem — no support
- 4. She's about right: both are corundum, ruby is the red kind — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 3 · right ✓
A cartoon shows a pirate digging up diamonds on a sandy beach next to a palm tree, "where diamonds grow". What should be corrected?
- 1. Diamonds form in the clouds and fall as hail — no support
- 2. Diamonds grow on trees, not in sand — no support
- 3. Diamonds only form inside ice in the Arctic — no support
- 4. Diamonds form about 150 km down and come up in volcanic pipes — ← Mova's choice · ✓ the right answer · score 3
Why: It took the question to ask what it is done to. It chose option 4 with score 3, the only option with support. Its support: lesson 51, line 7: «Until the 1700s almost all the world's diamonds came from India, from the Golconda region.», reached through the remembered sentence the question matched. What matched: the same action «come» (+3). · the question and its options parsed, with trees and pragmatics
Test 4 · right ✓
An old gold coin and an old iron nail are pulled from a shipwreck after 300 years. What will they probably look like?
- 1. Both shine like new — no support
- 2. The coin still shines, the nail is badly rusted — ← Mova's choice · ✓ the right answer · score 5
- 3. The coin is rusted, the nail shines — no support
- 4. Both are badly rusted and fall apart in your hand — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 5, the only option with support. Its support: lesson 51, line 4: «Gold, silver and platinum are precious metals. Gold never rusts, so a gold coin from a shipwreck still shines. But the story of gems and metals also has a dark…», reached through the option's own match among the sentences about the question's things. What matched: the same doer «gold coin» (+3); the same action «shine» (+2). · the question and its options parsed, with trees and pragmatics
Test 5 · wrong ✗
Mansa Musa, a famous king of Mali in the 1300s, was known for huge amounts of what?
- 1. Platinum from Russia — ← Mova's choice · no support
- 2. Diamonds from India — no support
- 3. Silver from Bolivia — no support
- 4. Gold — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 6 · wrong ✗
Mia's necklace has a fly stuck inside a golden-brown stone. What is the stone?
- 1. Quartz, a very common mineral — ← Mova's choice · no support
- 2. Topaz, a hard yellow crystal — no support
- 3. Ruby, a red kind of corundum — no support
- 4. Amber, fossil tree resin — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 7 · right ✓
"shut up, pearls come out of rocks like every other gem" — what is the truth?
- 1. Pearls are drops of melted silver that cooled — no support
- 2. Pearls are tiny diamonds — no support
- 3. Pearls are made by oysters and mussels, not rocks — ← Mova's choice · ✓ the right answer · score 6
- 4. Pearls form in volcanic pipes like diamonds do — no support
Why: It took the question to ask which statement is true. It chose option 3 with score 6, the only option with support. Its support: lesson 51, line 15: «Some gems are not minerals: amber is fossil tree resin, sometimes with insects trapped inside, and pearls are made by oysters and mussels.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «oysters» (+3); the same action «make» (+2); the same thing acted on «pearls» (+1). · the question and its options parsed, with trees and pragmatics
Test 8 · right ✓
What would happen if no one checked where diamonds came from?
- 1. Diamonds would slowly turn back into black carbon dust — no support
- 2. Diamonds mined to pay for wars could be sold freely — ← Mova's choice · ✓ the right answer · score 4
- 3. Diamonds would stop being hard — score 3
- 4. Diamonds would all become cheap glass — no support
Why: It took the question to ask where. It chose option 2 with score 4, against 3 for the next best. Its support: lesson 51, line 16: «Diamonds and other gems have paid for wars, so "conflict diamonds" are now meant to be tracked to show where they came from.», reached through the option's own match among the sentences about the question's things. What matched: the same action «pay» (+2); the same doer «diamonds» (+2). · the question and its options parsed, with trees and pragmatics
Test 9 · wrong ✗
A game shows Potosí as a happy mining town where everyone got rich. What is the true story?
- 1. It was mined by robots in the 1500s — ← Mova's choice · no support
- 2. It was a quiet farming village with no mine and no silver at all — no support
- 3. Its miners were all paid well and free — no support
- 4. Indigenous people were forced to mine it and many thousands died — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 10 · right ✓
Why is a car's exhaust part one of the places a thief might steal precious metal from?
- 1. It contains platinum, a metal rarer than gold — ← Mova's choice · ✓ the right answer · no support
- 2. It holds a tank of liquid silver — no support
- 3. It is made of solid gold under the paint — no support
- 4. It is full of emeralds — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 11 · wrong ✗
Which pair is made of the same mineral?
- 1. An emerald and a piece of amber — ← Mova's choice · score 5
- 2. A ruby and a sapphire — ✓ the right answer · score 5
- 3. A diamond and a sea pearl — score 5
- 4. A ruby and a green emerald — score 5
Why: It took the question to ask what it is done to. It chose option 1 with score 5, tied with another option at 5 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 50, line 1: «Rocks are made of minerals, the way a fruit cake is made of flour, sugar and raisins: a mineral is a natural solid with a fixed chemical makeup and its atoms a…», reached through the remembered sentence the question matched. What matched: the same circumstance (+4); the same action «make» (+3). Against it: a different thing acted on (counts against) (-2). The right option, 2, scored 5. · the question and its options parsed, with trees and pragmatics
Exam question 1 · formal language · right ✓
Identify the principal reason for which gold has been esteemed across several millennia.
- 1. It is resistant to corrosion and sufficiently malleable to be worked — ← Mova's choice · ✓ the right answer · score 5
- 2. It is the hardest substance hitherto discovered by mineralogists — no support
- 3. It is the most abundant metal in the Earth's crust — score 5
- 4. It emits light of its own accord — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 5, tied with another option at 5 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 51, line 11: «Gold does not rust or tarnish and is soft enough to shape, so it has been treasured for thousands of years.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «gold» (+3); the same action «shape» (+2). · the question and its options parsed, with trees and pragmatics
Exam question 2 · formal language · wrong ✗
Select the response that is consistent with the established facts concerning the origin of diamonds.
- 1. They are deposited by rivers upon the surface of deserts — ← Mova's choice · no support
- 2. They are secreted by marine molluscs — no support
- 3. They crystallise from carbon at great depth in the mantle and ascend through volcanic pipes — ✓ the right answer · no support
- 4. They precipitate from rainwater within caverns — no support
Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Exam question 3 · formal language · wrong ✗
Which of the following statements most accurately characterises rubies and sapphires?
- 1. Both are varieties of corundum, distinguished by trace elements — ✓ the right answer · no support
- 2. Both are varieties of beryl, distinguished by their age and depth — no support
- 3. Rubies are organic and sapphires mineral — ← Mova's choice · score 12
- 4. Sapphires are artificial and rubies natural — score 12
Why: It took the question to ask who or what does it. It chose option 3 with score 12, tied with another option at 12 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 51, line 8: «Rubies and sapphires are the same mineral, corundum; red corundum is ruby, and other colours are sapphire.», reached through the same lesson line as the sentence the question matched. What matched: it fills the role the question asks for (+5); the same doer «rubies» (+4); the same light verb (be, have, do, get, go) (+3). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Exam question 4 · formal language · wrong ✗
Pursuant to the tracking of so-termed "conflict diamonds", identify the purpose of such tracking.
- 1. To record the weight of each gem for taxation only — ← Mova's choice · no support
- 2. To ascertain the colour of each gem — no support
- 3. To demonstrate that gems have not financed armed conflict — ✓ the right answer · no support
- 4. To certify the hardness of each gem — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/geography/51-gemstones-and-precious-metals/